I'll bet this has been asked before

[HAL]

cubpilot,

You are right of course - I believe I have enough decision making ability to decide what is the right course of action, and am only looking for the exact legal interpetation. And I do think asking my POI is a good idea.

At the risk of overload, here the essence of my question is this: The FAR says (as deltoid pointed out) it is the weather at the estimated time of arrival that is important in making the decision (by 135.219) whether or not to take off. Now, if you have a five minute flight, the METAR says it is fine to go but the TAF forecasts below minumums, of course you can go. If it is a two hour flight, you can't go. My question is, where is the break between the 'current conditions' and forecast becoming predominant in making your decision.

I fully understand the 121 regs, as I've spent most of my career in 121 ops. Because of a furlough I'm now flying 135 and trying to make sure I don't confuse the issue between the two types of flying.

HAL

 

[avbug]

A METAR doesn't describe current conditions. It describes past conditions. Much like an annual inspection says about the current airworthiness of an airplane...the METAR speaks to the past. While the ink is wet on the signature of the IA performing the annual inspection, the aircraft can be unairworthy...the inspection buys the past, not the future. The same for the METAR. It speaks to the time of the observation, and no further.

The TAF, even if it covers the same time period, speaks to the future, and takes priority.

As for ceiling being controlling, it is never controlling. Even in the case of the high minimums captain; the captain isn't controlled by ceiling. Only visibility. However, one will have a harder time making the case that the flight visibility is above minimums when the ceiling is below the minimum descent altitude for the approach.

When a high minimums captain must add to the minimum descent altitude of decision altitude for the proceedure in use, no "ceiling" has been established for that captain. Only proceedural minimae.

The actual ceiling is no more limiting for a high minimums captain than it is for any other routine operation, weather Part 121 or Part 135.

What your POI has to say on the subject is opinion, but has no legal basis...and the POI has no authority to issue a "letter of interpretation." Visibility is controlling. One may be held to have violated the regulation where the ceiling is reported below minimums, as official data exists which shows that the lowest reported layer being broken or overcast, is below the minimum descent altitude for the proceedure...the burden of proof then comes on you to show that you had adequate visibility at the time...unless you take a photograph, you may be out of luck.

Remember that it's up to you to prove innocense; the FAA doesn't need to prove it's case, as the circumstantial facts of a report below minimums are more than enough. You are guilty until proven innocent, and you may require more than an "I had the required visual references in sight" to counter an official weather report or observation, to the contrary.

 

[Deltoid]

Hi Hal,

This is the most you will get out of the FAA on the subject of departure decision making.

The rationale behind the current regulation is that as long as one can show a combination of weather reports or forecasts indicating above minimum weather conditions at the estimated time of arrival (ETA) at the destination airport, the flight may be dispatched or released. However, the converse is also true, that when any combination of weather reports or forecasts show below minimum weather conditions at the destination airport at ETA, the aircraft may not be dispatched or released.

The key thing is ETA and no part of the forecast including prob40 or temp can have anything below mins. Metars may be past info but it is a report never the less. When its provided by an A02 system you can call the number to get a live report. Thats what I would do. Also get past Metars to paint a weather trend picture and see if its contrary to or in line with the forecast. You can even get a weather depiction chart off these WSI stations to see whats happening around the airfield. Its a report as well. It may be a little stale but you can see the surface front positions and surround conditions.

Avbug writes:

"As for ceiling being controlling, it is never controlling. Even in the case of the high minimums captain; the captain isn't controlled by ceiling. Only visibility. However, one will have a harder time making the case that the flight visibility is above minimums when the ceiling is below the minimum descent altitude for the approach. BINGO !!!!!!

When a high minimums captain must add to the minimum descent altitude of decision altitude for the proceedure in use, no "ceiling" has been established for that captain. Only proceedural minimae. " Correct.....

Your right about visiblity controlling but my point is that the FAA violated our guys because the high min captain shot an approach to a 100 & 1 reported cat I because he was on low fuel and had not declared an emergency to deviate from 121.652. They got him on going below his 300' limit. Their reasoning is excactly what you mentioned about how will you have a mile vis with a ceiling below your limit. They contended he should not have started the approach and deverted or delcared a fuel emergency giving him carte blanc... Thats why our high mins guys will not start the approach when the ceiling is below the high mins limit. Otherwise its reported visiblity for non high mins guys to begin the approach.

This is great discussion. Keeps me up on this..

Good day Guys.

Deltoid

 

[AAsRedHeadedbro]

Just to add a quick two cents to this discussion, under current FAR part 121 dispatch rules along with a certain exemption given to my carrier (I believe it's 3585 but I can not be absolutely certain since I don't have my ops specs with me at home), we are allowed to depart for the destination airport when the CONDITIONAL language of the forecast indicates that the visibility may be below that required for an approach to that airport (The MAIN body of the forecast must indicate visibility at or above the minimum visibility value for the planned approach). The exemption requires that the visibility value in the conditional section be no less than 1/2 the required visibility for the planned approach and requires a SECOND alternate to be filed. The exemption goes on to say that the forecast for the FIRST alternate airport must indicate in the conditional remarks section values of no less than 1/2 the required visibility AND ceiling required for the planned approach to be used. Additionally, the SECOND alternate must indicate that visibility AND ceiling will be at or above minimums for the approach planned for that airport in both the main body AND the conditional remarks section. No reductions of any kind are allowed for the second alternate with respect to dispatch requirements.

So it appears that the FAA has allowed exemptions to be used at some (if not all) part 121 air carriers with regards to dispatch to destination airports that are forecast to possibly be below minimums, based on conditional language. The FAA apparently has modified its stance somewhat since the letters posted by Avbug were first published in the late 1980's.

 

[DavidP]

outdated letter

Mr. John G. Butler, III
Sands Anderson PC
Office of the Chief Counsel
Post Office Box 1998
Richmond, YA 23 218-1998
Dear Mr. Butler,
800 Independence Ave., S.W.
Washington, D.C. 20591
This letter responds to your request for a legal interpretation regarding the minimum weather
conditions for initiating an instrument approach under 14 CFR § 135.225. You asked
whether a Part 135 pilot may legally commence an instrument approach if the reported
visibility is at, or greater than, the minimum visibility published for the approach, even if the
reported ceiling is below the published decision height.
The FAA finds that the reported ceiling is not a weather condition to be considered as a
landing or approach minimum unless it is expressly referenced in the approach procedure or
other operating limitation. Based on our research, the FAA concludes that a previous leg~
interpretation did not accurately interpret the meaning and intent of 14 CFR § 135.225. See
Legal Interpretation to Glenn Rizner from Donald P. Byrne, Assistant Chief Counsel for ·
Regulations and Enforcement (March 21, 1991 ). The current legal interpretation takes
precedence over any prior interpretations reaching a different conclusion, specifically the
1991 Legal Interpretation to Glenn Rizner.
Your inquiry is directed at 14 CFR § l 35.225(a), which prohibits a pilot conducting a Part
135 operatien from initiating an instrument approach unless (1) the airport has an
appropriate weather reporting facility, and "(2) [t]helatest weather report issued by that
weather reporting facility indicates that weather conditions are at or above the authorized
minimums for that airport." Thus, the issue becomes whether "weather conditions" as used
in§ 135.225(a)(2) includes the reported ceiling.
Prior to the implementation of Terminal Instrument Procedures (TERPs) in 1967, instrument
approach procedures included ceiling values as part of the landing minimums. TERPs
established minimum descent altitude (MDA) and decision height, in place of landing
ceiling minimums, while retaining the visibility as the applicable landing minimum. 32 Fed.
Reg. 13909 (Oct. 6, 1967). The adoption ofTERPs as an amendment to Part 97 (adding
subpart C) began the conversion of ceiling values to MDA and decision height for all
existing standard instrument approach procedures listed in Part 97, subpart B. Id. at 13909-
10 .. The 1967 rulemaking also amended Parts 121 and 135, substituting "weather
conditions" for "ceiling and ground visibility" in the provisions dealing with instrument
operations, to allow for either or both values to be considered depending on the
circumstances of the operation. Id. at 13910; see also Legal Interpretation to James B. Hart
from Rebecca B. MacPherson, Assistant Chief Counsel for Regulations (April 21, 2009).
2
Furthennore, the current version of Part 97 does not consider the ceiling as a factor for
initiating an approach, as it defines ceiling as "the minimwn ceiling, expressed in feet above
the airport elevation, required for takeoff or required for designating an airport as an
alternate airport. See I~ CFR § 97.3. Using the term "weather conditions" in
§ 135.225(a)(2) leaves open the potential applicability of ceiling values to allow for
conversion of Part 97 for each approach procedure and for other operations requirements,
such as operations specifications, that might incorporate ceiling values.
Each standard instrument approach procedure (SIAP) is authorized through Part 97, specific
to the airport and runway. Part 97 authorizes the instrument approach, graphically depicted
in the approach plate, and determines the authorized minimwns. Your letter represents that
the approach reflects a decision altitude, decision height, and visibility for an instrument
landing system (ILS) approach at an airport you do not identify. You also indicate that the
ceiling is not a criterion on the approach plate: We must asswne that your reading of the
approach plate is accurate, since your letter does not identify the airport, runway, and
aircraft approach speed category. Based on the representations contained in your letter, the
FAA concludes that a pilot may legally commence the instrument approach you describe
regardless of the reported ceiling, if no operational requirement apart from the SIAP
imposes a ceiling value limitation.
We appreciate your patience and trust that the above responds to your concerns. This ·
response was coordinated with the Air Transportation and the Flight Technologies and
Procedures Divisions of Flight Standards Service. Should you have any further questions,
please contact Nancy Sanchez, an attorney in the Regulations Division of the Office of the
Chief Counsel, at (202) 267-3073.
Sincerely,
/4r--9-)j/~
Rebecca B. MacPherson
Assistant Chief Counsel for Regulations, AGC-200

 

[DavidP]

"Based on our research, the FAA concludes that a previous leg~
interpretation did not accurately interpret the meaning and intent of 14 CFR § 135.225. See
Legal Interpretation to Glenn Rizner from Donald P. Byrne, Assistant Chief Counsel for ·
Regulations and Enforcement (March 21, 1991 ). The current legal interpretation takes
precedence over any prior interpretations reaching a different conclusion, specifically the
1991 Legal Interpretation to Glenn Rizner."

 

[FlyBigE]

late to the party on this one. I have flown under 121 and 135 and don't recall the ceiling ever being an issue domestically. Internationally it can be regulatory and will state CEILING REQUIRED on the approach plate. It is very interesting the Feds tried to prosecute on the ceiling alone.

The controlling reg for 121 is 121.613 and 121.615. Which basically say Flights will be not be dispatched or released unless appropriate weather reports or forecasts, or any combination thereof, indicate weather conditions will be at or above the authorized minimums at the estimated time of arrival at the airport or airports to which
dispatched or released.

The airlines have several Exemptions and I believe 135 operators can apply for them as well. YMMV

Regulatory Docket No. FAA-2001-9379 Effective June 1, 2023, Exemption 3585 is amended to be named Exemption 20108.

Exemption 20108 can never be used with HIGH MINS CAPTAINS

Airlines also use Exception 17669 which gives relief to file an alternate domestically by reducing wx requirements. One hour before to one our after an alternate is not required if the destination is
Cat 1- 1000/3sm
Cat 2/3 - 1000/2sm
(no TS are forecast)

Exemption 5549 which allows for high min Captains to be dispatched to airfields based on Cat I or II ops and conduct Cat I or II ops to the lowest publish minimums allowed by the approach plate, nav facility, or aircraft capability.

 

[FlyBigE]

"Based on our research, the FAA concludes that a previous leg~
interpretation did not accurately interpret the meaning and intent of 14 CFR § 135.225. See
Legal Interpretation to Glenn Rizner from Donald P. Byrne, Assistant Chief Counsel for ·
Regulations and Enforcement (March 21, 1991 ). The current legal interpretation takes
precedence over any prior interpretations reaching a different conclusion, specifically the
1991 Legal Interpretation to Glenn Rizner."

can you post the current legal interpretation?

 

[midlifeflyer]

can you post the current legal interpretation?

https://www.faa.gov/sites/faa.gov/files/faa_migrate/interps/2011/Butler-SandsAnderson_2011_Legal_Interpretation.pdf

 

[FlyBigE]

Thank you